But Josh faces challenges most of his peers don't: he has autism, as well as attention deficit hyperactivity disorder, oppositional defiance disorder, and anxiety.

His mum, Christina Duffy, said it had been "really hard". Unlike physical conditions, she said, it was a lot more difficult to have something like autism recognised and addressed.

"It's an invisible disability, really," Mrs Duffy said.

Read more: Parents of kids with autism 'need more help'

He was first assessed as having mild autism, Mrs Duffy said, but with more insight and a new paediatrician, it was diagnosed at being at a higher level, as well as the other conditions.

Josh started his education in mainstream school, which was "terrible", and has since been at three other schools. He now attends for two hours each morning.

Mrs Duffy said the wait to get Josh diagnosed was not "too bad", but the wait for other services was long. He undertakes behavioural therapy and occupational therapy each week.

He also used to have weekly speech therapy, but when his therapist moved to a different job he was put onto a waiting list and he hasn't had speech therapy in over a year. He also only recently started a new occupational therapist after his last one moved in June.

Mrs Duffy said these therapies were massively important; they gave her son the skills he needed to get through life. But she said there was a significant shortage of these practitioners in the Illawarra.

This is something Figtree mother Amanda Di Noro has also experienced. Mrs Di Noro's sons Xavier, 11, and Christiano, 9, both have autism; Xavier was diagnosed when he was two and a half, and Christiano was diagnosed at the age of four.

Mrs Di Noro said it was difficult to even obtain a referral in order to get the diagnosis process under way, and without the diagnosis, it was hard to get help.

Read more: A month to shift the perception of autism

"It's a really frustrating and awful journey," she said, adding that waiting lists were "ridiculous".

Mrs Di Noro said they spent 10 months on a waiting list to get a spot in an occupational therapy program, but struck it lucky for Xavier when they found a speech pathologist who had just started their own practice.

She wants to get Christiano into speech pathology, too, but nothing is available.

Early intervention was recommended as the best measure, Mrs Di Noro said, but there were not enough services available in the region for children to get the help they needed. She said online support groups were busy with people asking where they could access services for their child.

Mrs Di Noro said these services were important before children headed to school, because they gave them more confidence to go into an environment they were uncomfortable in.

But a lack of support was not only detrimental for the child, she said - it affected the whole family.

Albion Park parents Sonya and Tony Caldeira struggled too to get their son Kayden, now seven, assessed and diagnosed.

Despite taking their concerns about their son's development to a paediatrician when he was two-years-old, they were told to come back when he was four, before he started school.

"I knew that my child wasn't functioning properly," Mrs Caldeira said. "I just didn't know what was wrong. I ended up paying out of pocket to see a specialist for an assessment. That paediatrician had observed Kayden in the waiting room and as we walked in he said 'So you're here for an autism assessment, and I said 'I guess we are'."

Receiving the diagnosis was important, but also traumatic and overwhelming.

"We were told our child would never function in any normal capacity, we were told he would never speak," Mrs Caldeira said.

"But while he has limitations, on a good day we have a seven-year-old who is so unique, who doesn't stop talking.

"And we credit that with the early intervention we were able to access once he was diagnosed."

Around 80 per cent of the therapies Kayden needs are covered by the NDIS; the couple needs to fund the shortfall. Plus if they want services when they're needed, they also have to pay for private specialists rather than face long waiting lists.

"For instance we've been trying to get our son assessed by a psychologist, but there's at least a six-month waiting period," Mrs Caldeira said. "It's an ongoing struggle to get him the support he needs."

Cathy Kerr, from Bulli's Branch Support Services, has heard the same feedback from parents and carers. She told the Mercury that people reported long wait times for speech therapy, occupational therapy and psychology in the region.

"These services are invaluable to supporting the therapy needs of individuals with additional needs, and to enabling participants to work towards their NDIS plan goals," she said.

Branch Support Services does not provide therapies, but training, coaching and mentoring in relation to social and functional life skills which are complementary to the skills children and adults learn in therapy.

Speech pathologist Briana McMillan works as part of a private multidisciplinary autism assessment team and said they were booked out until September. At her practice, Let's Talk Speech Pathology, there was a wait of two to three months for therapy.

She said there was a shortage of clinicians in the Illawarra. The NDIS also meant people had more money to spend on therapies, which added to demand.

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